Which of the group element does not form M(III) iodide?

Question

Which of the group element does not form M(III) iodide? (A) Al (B) Ga (C) In (D) Tl

Tardigrade Admin · Accepted Answer

Due to inert pair effect, textTl prefers its text+1 oxidation state while bonding with iodine and textTlI form. Although thallium text(Tl) form TlI3 , but the O.S. of thallium is text+1 in this compound, because iodine is present as tri-iodide ion (I3-).

Q. Which of the group element does not form M(III) iodide?

Al

Ga

In

Tl

Due to inert pair effect, $Tl$ prefers its $+1$ oxidation state while bonding with iodine and $TlI$ form. Although thallium $(Tl)$ form $Tl I_{3}$ , but the O.S. of thallium is $+1$ in this compound, because iodine is present as tri-iodide ion $(I_{3}^{-}) .$

Q. Which of the group element does not form M(III) iodide?

Al

Ga

In

Tl

Due to inert pair effect, Tl prefers its +1 oxidation state while bonding with iodine and TlI form. Although thallium (Tl) form TlI3​ , but the O.S. of thallium is +1 in this compound, because iodine is present as tri-iodide ion (I3−​).

Due to inert pair effect, $Tl$ prefers its $+1$ oxidation state while bonding with iodine and $TlI$ form. Although thallium $(Tl)$ form $Tl I_{3}$ , but the O.S. of thallium is $+1$ in this compound, because iodine is present as tri-iodide ion $(I_{3}^{-}) .$